1. Field
The invention is in the field of battery chargers and also in the field of electrical motors, particularly power supplies therefor.
2. State of the Art
Battery chargers operate by applying a reverse voltage to a battery and forcing current to flow backwardly in the battery, thereby reversing the normal ion exchange process and returning the ions to their original positions. This, then, replenishes the reservoir of electrons at the negative plates so that they can again flow when the battery is connected to power a circuit. However, as a battery discharges, a resistive film forms on the surfaces of the plates in the battery. Battery chargers use either a steady D.C. voltage or a rectified A.C. voltage to create a reverse D.C. current in the battery. The normal charging process does nothing to eliminate or reduce the resistive film. When reverse current is applied to the battery, such current must flow through the resistive film. The rate of charge in a battery is determined by the rate of reverse current flow. Such current flow is limited by the heat generated in the battery. Most heat generated in the battery is caused by the current flow through the resistive film and such heat can build up to the point where is causes warping, buckling, or other distortion and physical damage to the plates in the battery or even to the battery casing. In addition, the heat generated in the battery increases the natural decay of the battery plates into the electrolyte which further reduces battery life. In many instances, 65-70% of the charging current in a battery is used up in flow across the resistive film. This leaves only 30-35% of the current to actually charge the battery. In addition, after extended use of the battery or substantial discharge of the battery, the resistive film becomes so thick that substantially all of the current flow is used in overcoming the resistance and nothing goes to charging the battery. In such instance, even if the battery is charged, the resistance prevents useful discharge of the battery so the battery is considered as dead and not able to take a charge. Because of the resistive film, most battery charging takes longer than in many cases one would like it to, and with many batteries, charging does no good.
With equipment powered by electric motors, the motors are rated for use at a certain voltage and use with voltages over the rated voltage causes motor burn-out. There is no known way to substantially increase the power a motor can deliver without increasing voltage, which will usually result in burn-out. It is known that with stepping motors an initial, short, high voltage pulse followed by the normal rated voltage increases the response time of the motor, but does not increase power or torque of the motor.